Data di Pubblicazione:
2019
Citazione:
MOLECULAR AND CELLULAR MECHANISMS REGULATING EPIGENETIC CELL CONVERSION / E.f.m. Manzoni ; tutor: F. Gandolfi ; supervisore: T. Brevini ; coordinatore: F. Gandolfi. DIPARTIMENTO DI SCIENZE AGRARIE E AMBIENTALI - PRODUZIONE, TERRITORIO, AGROENERGIA, 2019 Feb 28. 31. ciclo, Anno Accademico 2018. [10.13130/manzoni-elena-franca-maria_phd2019-02-28].
Abstract:
Phenotype definition is controlled by epigenetic regulations that allow
cells to acquire their differentiated state. The process is reversible and
cells can be driven back to a higher plasticity state with several different
approaches, which include the interaction with the epigenetic set up
through the use of epigenetic erasers, readers or writers. Among the
many epigenetic modifiers presently available, in our previous
experiments, we selected 5-azacytidine (5-aza-CR), which is a well-known
DNA methyltransferase inhibitor, and has been previously shown to
increase cell plasticity and facilitate phenotype changes in different cell
types.
Beside the epigenetic mechanisms driving cell conversion processes,
growing evidences highlight the importance of mechanical forces that
directly influence cell plasticity and differentiation. Aims of my PhD
were: a) characterization of the molecular and cellular mechanisms
regulating cell phenotype b) analysis of the possible relation between
mechano-sensing and epigenetic control of cell plasticity and
differentiation. The experiments carried out confirmed the global
demethylating effect of 5-aza-CR, with a transient upregulation of
pluripotency markers. At the same time increased transcription of TET2
and several histones was detected. This was accompanied by changes in
enzymes controlling histone acetylation and cell morphological
rearrangement. Interestingly, the study of DNA methylation profile and
its regulatory genes, revealed that the use of a 3D micro-bioreactor
promotes and stabilizes the maintenance of the acquired plasticity for a
long period of culture. In particular, the use of an adequate soft substrate increased pancreatic conversion efficiency and induced the acquisition of
a mono-hormonal phenotype, which is distinctive of terminally matured
cell. Altogether these findings indicate that 5-aza-CR induced somatic cell
transition to a higher plasticity state may be the result of multiple
regulatory mechanisms that accompany the demethylating effect exerted
by the modifier. The results described in my thesis also revealed that
mechano-transduction-related responses modulate and maintain 5-aza-
CR induced cell plasticity and significantly improve cell differentiation
toward the pancreatic lineage.
Tipologia IRIS:
Tesi di dottorato
Elenco autori:
E.F.M. Manzoni
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